Cavernous Malformation of the Hypoglossal Nerve: Case Report and Review of the Literature

Cavernous Malformation From Cranial Nerves: A Systematic Review With a Novel Classification and Patient-Level Analysis

BACKGROUND AND OBJECTIVES

Cavernous malformations (CMs) occurring in the cranial nerve (CN) are extremely rare, and there is currently no comprehensive review on CN CMs, leading to a lack of sufficient understanding of CN CMs. We aimed to systematically review all published CN CM cases; summarize the epidemiology, clinical manifestations, treatment, and prognosis of CN CMs; and identify factors influencing the prognosis of CN CMs.

METHODS

This systematic review identified all cases potentially diagnosed with CN CM through a systematic search of PubMed, SCOPUS, Web of Science, and Cochrane databases. This represents the most comprehensive systematic review to date. We classified CN CMs based on their anatomic origins. Patient characteristics, disease manifestations, treatment approaches, and prognosis were summarized descriptively. Further analysis was conducted to identify factors influencing the prognosis of CN CMs.

RESULTS

The final analysis included 108 articles (127 individual patient cases). The optic nerve (49/128, 38.3%) is the most commonly affected nerve. Notably, CN CMs can be categorized into 3 types: Intraneural, Perineural, and Extraneural. Preoperative nerve function status and novel classification were associated with the prognosis of CN CMs (P = .001; P < .001). The postoperative neurological deterioration rate for the Intraneural type was 19/37 (51.4%); for the Extraneural type, it was 13/69 (18.8%); and for the Perineural type, it was 1/22 (4.5%) (P < .001).

CONCLUSION

We reviewed all the published CN CMs to date, offering a comprehensive description of CN CMs for the first time and identifying prognostic factors. The classification of CN CMs proposed in this study could serve as guidance for the selection of intraoperative treatment regimens. The findings of this systematic review are expected to provide a foundation for clinical decision-making in this crucial rare disease and lay the groundwork for developing relevant clinical guidelines.

An isolated cavernous malformation of the sixth cranial nerve: A case report and review of literature

Background

Isolated cavernous malformation (CM) of the abducens nerve has not been reported in the literature. Herein, the authors address the clinical importance of these lesions and review the reported cases of CM from 2014 to 2020.

Case Description

A 21-year-old man presented with binocular diplopia and headache from 2 months before his admission. The neurological examination revealed right-sided abducens nerve palsy. The brain MRI revealed an extra-axial pontomedullary lesion suggestive of a CM. The lesion was surgically removed. During the operation, the abducens nerve was resected considering the lesion could not be separated from the nerve and an anastomosis was performed using an interposition nerve graft and fibrin glue. Pathological examination of the resected lesion revealed that it was originated from within the nerve. The patient's condition improved in postoperative follow-ups.

Conclusion

Surgical resection of the cranial nerves CMs is appropriate when progressive neurological deficits are present. If the lesion is originated from within the nerve, we suggest resection of the involved nerve and performing anastomosis. Novel MRI sequences might help surgeons to be prepared for such cases and fibrin glue can serve as an appropriate tool to perform anastomosis when end-to-end sutures are impossible to perform.

Calcified extra-axial cavernous malformation arising from lower cranial nerves: A case report and literature review

RATIONALE

Extra-axial cavernous malformations (ECMs) arising from cranial nerves (CNs) are rare. Complete "en bloc" lesion resection and hemosiderin-stained tissue preservation remain the standard treatment, while a different strategy may be needed when the lesion is highly calcified . We report the 3rd calcified ECM-CN and review the clinical features and surgical strategy for this rare condition considering previous literature.

PATIENT CONCERNS

We present a 52-year-old woman with a calcified lesion located in the right lower 1/3 of the cerebellopontine angle.

DIAGNOSIS

The diagnosis was calcified ECM-CNs according to the pathological and radiological features.

INTERVENTIONS

A posterior midline craniotomy was performed, and piecemeal resection of the lesion was carried out. Subtotal resection of the lesion was achieved with a small piece left in situ.

OUTCOMES

No symptom or lesion-related recurrence was found during 28 months of follow-up.

LESSONS

Calcified ECM-CNs are unique cavernous malformations arising from CNs. Piecemeal resection and subtotal or near-total excision are 2 major aspects that differ from the surgical strategy for general ECM-CNs.

Guidelines for radiographic imaging of cranial neuropathies

Disruption of the complex pathways of the 12 cranial nerves can occur at any site along their course, and many, varied pathologic processes may initially manifest as dysfunction and neuropathy. Radiographic imaging (computed topography or magnetic resonance imaging) is frequently used to evaluate cranial neuropathies; however, indications for imaging and imaging method of choice vary considerably between the cranial nerves. The purpose of this review is to provide an analysis of the diagnostic yield and the most clinically appropriate means to evaluate cranial neuropathies using radiographic imaging. Using the PubMed MEDLINE NCBI database, a total of 49,079 articles' results were retrieved on September 20, 2014. Scholarly articles that discuss the etiology, incidence, and use of imaging in the context of evaluation and diagnostic yield of the 12 cranial nerves were evaluated for the purposes of this review. We combined primary research, guidelines, and best practice recommendations to create a practical framework for the radiographic evaluation of cranial neuropathies.

Radiology and imaging for cavernous malformations

Cavernous malformations are low-flow vascular malformations that are histologically characterized by the lack of mural elements of mature vascular structures and intervening parenchymal neural tissue. They are often clinically quiescent, and may grow, bleed, and regress, but can also manifest clinically as neurologic deficits or seizures in the setting of an acute hemorrhage. The low-flow nature of cavernous malformations renders them inherently occult on cerebral angiography. Magnetic resonance imaging has become the mainstay imaging modality in evaluating cavernous malformations, producing characteristic imaging features that usually provide a straightforward diagnosis. Features on magnetic resonance imaging include a reticulated pattern of mixed hyper- and hypointensity on T1- and T2-weighted imaging, with a characteristic hypointense rim best appreciated on T2-weighted imaging or gradient-echo sequences. Contrast enhancement is useful for revealing coexisting developmental venous anomalies that are frequently associated with sporadic cavernous malformations, and may further support the diagnosis. Susceptibility-weighted imaging is highly sensitive for cavernous malformations and accompanying developmental venous anomalies, and is superior to gradient-echo sequences in screening for multifocal, familial cavernous malformations.

Angiographically occult vascular malformation of the intracranial accessory nerve: case report

Angiographically occult cerebral vascular malformations (AOVMs) are usually found in the supratentorial brain parenchyma. Uncommonly, AOVMs can be found within the cavernous sinus or basal cisterns and can be associated with cranial nerves. AOVMs involving the intracranial segment of the spinal accessory nerve have not been described. A 46-year-old female patient presented with a history of episodic frontal headaches and episodes of nausea and dizziness, as well as gait instability progressing over 6 months prior to evaluation. Imaging revealed a well-circumscribed 3-cm extraaxial T1-weighted isointense and T2-weighted hyperintense contrast-enhancing mass centered in the region of the right lateral cerebellomedullary cistern. The patient underwent resection of the lesion. Although the intraoperative appearance was suggestive of a cavernous malformation, some histological findings were atypical, leading to the final diagnosis of vascular malformation, not otherwise specified. The patient's postoperative course was uneventful with complete resolution of symptoms. To the authors' knowledge, this is the first report of an AOVM involving the intracranial portion of the accessory nerve. For any AOVM located within the cerebellomedullary cistern or one suspected of involving a cranial nerve, the authors recommend including immunohistochemistry with primary antibody to neurofilament in the histopathology workup.

Cavernous malformations isolated from cranial nerves: Unexpected diagnosis?

OBJECTIVES

Cranial nerves (CN) cavernous malformations (CMs) are lesions that are isolated from the CNs. The authors present three cases of CN CMs, for which MR was demonstrated to be critical for management, and surgical resection produced good outcomes for the patients. Surgical removal is the recommended course of action to restore or preserve neurological function and to eliminate the risk of future haemorrhage. However, the anatomical location and the complexity of nearby neural structures can make these lesions difficult to access and remove. In this study, the authors review the literature of reported cases of CN CMs to analyse the clinical and radiographic presentations, surgical approaches and neurological outcomes.

PATIENTS AND METHODS

A MEDLINE/Pub Med search was performed and revealed 86 cases of CN CMs. The authors report three additional cases in this study for a total of 89 cases. CMs affecting the optic nerve (CN II), oculomotor nerve (CN III), facial/vestibule-cochlear nerves (CN VII, CN VIII) have been described. The records of three patients were reviewed with respect to the lesion locations, symptoms, surgical approaches and therapeutic considerations. Clinical and radiological follow-up results are reported. Three patients (2 females, 1 male; age range 21-37 year) presented with three CN lesions. One lesion involved CN III, one lesion involved CN VII-CN VIII, and one involved CN II. The patient with the CN III lesion had a one-month history of mild right ptosis and diplopia. The patient with the CN VII-CN VIII lesion exhibited acute hearing loss and on the left and left facial paresis. The patient with the opticchiasmatic lesion presented with acute visual deterioration on the right and a left temporal field deficit in the left eye. Pterional and orbitozygomatic craniotomies were performed for the CN III lesion and the CN II lesion, and retrosigmoid craniotomy was performed for the cerebello-pontine angle lesion.

RESULTS

All patients experienced symptom improvement after surgery. On MR follow-up, recurrence was excluded in all patients.

CONCLUSIONS

CN CMs present with specific symptoms and require complex surgical techniques for resection. These lesions are frequently symptomatic, because of the complexity of the origin tissue. Symptomatic CN CMs should be resected microsurgically and completely when possible to prevent further losses of nerve function, improve function, avoid recurrence, and to eliminate the risk of future haemorrhages. The authors discuss the therapeutic options and the radiological features of these infrequent localisation of CMs. Specifically, the authors focus on the role of magnetic resonance imaging in the identification of these rare lesions.

Cavernous Hemangioma of the Abducens Nerve: Clinical Implication of Duplicated Variants: Case Report

BACKGROUND AND IMPORTANCE:

A cavernous hemangioma arising from the abducens nerve has not been previously reported in the literature. Based on the surgical experience with this case, the authors discuss the clinical importance and resectability potential of a duplicated abducens nerve.

CLINICAL PRESENTATION:

A 54-year-old woman presented with a recurrence of diplopia that had occurred 3 years before this admission and had spontaneously resolved without any specific treatment. On admission, there were no specific neurological deficits. Magnetic resonance imaging revealed a cone-shaped mass on the right anterior cerebellopontine angle with hemorrhagic change. Surgical resection via a standard right lateral suboccipital approach was performed. A cystic mass was found emerging from the entry zone of the Dorello canal and encircling the larger branch of the duplicate abducens nerve. Because there was no demarcation between the mass and origin branch, both were removed en bloc. Pathology revealed the presence of a cavernous hemangioma mixed with nerve tissue. Despite preserving a small branch of the duplicate abducens nerve, the patient had permanent right abducens palsy.

CONCLUSION:

A cavernous hemangioma arising from the abducens nerve should be suspected as a possible diagnosis for a cystic mass on the anterior cerebellopontine angle. Although duplication of the abducens nerve has not been clearly confirmed on clinical grounds, sacrificing the larger branch during surgery may lead to permanent abducens palsy, as in our case.

Cavernous Malformation of the Trochlear Nerve: Case Report and Review of the Literature on Cranial Nerve Cavernomas

BACKGROUND AND IMPORTANCE:

Cavernous malformations (CMs) arising intrinsically to the cisternal segment of the trochlear nerve are extremely rare. This case of a trochlear nerve cavernous angioma is the third to be reported in the neurosurgical literature and the first to be resected by a middle fossa approach.

CLINICAL PRESENTATION:

The authors present a case of a 31-year-old woman with progressive left-sided headache and left hemisensory symptoms, whose magnetic resonance imaging showed a solid enhancing tumor in the left ambient cistern at the level of the midbrain-pontine junction causing significant brainstem compression. Intraoperatively, a left trochlear nerve cavernous angioma circumferentially enveloping the nerve was visualized. The angioma was microsurgically resected by a middle fossa approach under frameless stereotactic guidance. Gross total resection of the intrinsic trochlear nerve lesion was achieved, although the trochlear nerve could not be preserved intact.

CONCLUSION:

CMs should be considered in a possible differential diagnosis of cisternal trochlear nerve tumors. Surgical resection remains the standard of care, and is indicated for relief of compressive symptoms and prevention of future bleeds. Postoperative diplopia often persists; however, resolution of diplopia reported in the literature can be attributed to either regeneration after direct surgical repair of the sacrificed nerve or a spontaneous adaptation over time.

Removal of cavernous malformation of the Meckel's cave by extradural pterional approach using Heros muscle dissection technique

BACKGROUND

We report on a patient with trigeminal neuralgia caused by an extraaxial cavernous malformation (CM) located within Meckel's cave. The lesion was removed via a pterional extradural approach with a modified temporalis muscle dissection technique, which was first described by Heros and Lee. Cadaveric dissections were performed to demonstrate the wider exposure gained by this approach.

METHODS

A 56-year-old man presented with a history of episodic shocklike, right-sided facial pain for 10 years. Neurologic examination revealed diminished sensation in the mandibular division of the right trigeminal nerve. Magnetic resonance imaging showed an ipsilateral enhancing lesion in Meckel's cave.

RESULTS

After placement of a lumbar drain, a right extradural pterional approach was undertaken. By reflecting the temporalis muscle posterolaterally, the craniotomy was extended so that the line of sight was level with the floor of the middle fossa. This allowed access to the lesion without needing to remove the zygoma. The lesion was resected with microsurgical technique. The patient's pain improved significantly after resection, and histopathologic examination confirmed the diagnosis of CM.

CONCLUSIONS

Extraaxial middle fossa CMs arising solely from Meckel's cave are rare. These lesions are safely and simply approached by posteriorly deflecting the temporalis muscle during a pterional craniotomy, avoiding excessive elevation of the anterior temporal lobe or further bony removal.

Calcified extra-axial cavernoma involving lower cranial nerves: technical case report

OBJECTIVE

Extra-axial cavernomas involving cranial nerves (CNs) are uncommon vascular malformations and may cause neurological deficits. We report what is, to our knowledge, a unique case of a calcified extra-axial cerebellopontine angle (CPA) cavernoma involving the lower CNs.

CLINICAL PRESENTATION

A 48-year-old man was admitted to our department with a 5-month history of gait instability and loss in tone of voice. A clinical examination documented gait disturbances and hoarseness but was otherwise unremarkable. Neuroradiological studies revealed a calcified mass in the lower third of the CPA cistern that was angiographically occult. It was associated with 3 additional lesions with a radiological appearance suggestive of multiple cavernomas.

INTERVENTION

The patient underwent a retrosigmoid approach, and the calcified mass, tightly adherent to the lower CNs, was gently removed. The histopathological examination was consistent with a cavernoma. The postoperative course was characterized by a further lowering in the patient's tone of voice. At the 3-month follow-up examination, the patient showed significant improvement.

CONCLUSION

CPA cavernomas are an extremely rare entity. Symptoms are generally related to CN compression, and subarachnoid hemorrhage is a very rare occurrence. The clinical and radiological appearance may mimic that of other CPA tumors (meningiomas, schwannomas). In spite of the benign nature and the very low risk of hemorrhage, we believe, with support from the literature, that surgical treatment is mandatory to prevent significant neurological deficits owing to the chronic CN compression.

Optochiasmatic cavernous angioma: unexpected diagnosis. Case report

A 15-year-old boy presented with an extremely rare optochiasmatic cavernous angioma. He was admitted to a special hospital with the complaint of blurred vision persisting for 1 month. Magnetic resonance imaging and biopsy of the lesion were inconclusive. He was admitted to our neurosurgical clinic after worsening of the visual symptoms 9 months later. Repeat magnetic resonance imaging showed optochiasmatic cavernous angioma which had doubled in size. The lesion was removed completely without any problem. Postoperatively his visual complaints remained stable, but had improved after 1 year. Optochiasmatic cavernous malformation should be treated by surgical excision, whereas biopsy is useless and may result in enlargement.

Cavernous Malformation of the Trigeminal Nerve Manifesting with Trigeminal Neuralgia: Case Report

OBJECTIVE AND IMPORTANCE:

We describe a patient with a cavernous malformation within the trigeminal nerve at the nerve root entry zone who presented with trigeminal neuralgia.

CLINICAL PRESENTATION:

A 52-year-old woman sought treatment after experiencing dizziness and lancinating left facial pain for almost a year. Neurological examination revealed diminished sensation in the distribution of the trigeminal nerve on the left. Magnetic resonance imaging demonstrated a minimally enhancing lesion affecting the trigeminal nerve.

INTERVENTION:

The patient underwent a retrosigmoid craniotomy. At the nerve root entry zone, the trigeminal nerve was edematous with hemosiderin staining. The lesion, which was resected with microsurgical technique, had the appearance of a cavernous malformation on gross and histological examination. The patient's pain improved significantly after resection.

CONCLUSION:

Cavernous malformations can afflict the trigeminal nerve and cause trigeminal neuralgia. Microsurgical excision can be performed safely and is associated with improvement in symptoms.

Surgical management of cavernous malformations involving the cranial nerves

OBJECTIVE

To analyze the indications and techniques pertinent to the treatment of cranial nerve (CN) cavernous malformations (CMs).

METHODS

CN CMs are lesions isolated to the CNs. CMs affecting the optic nerve (CN II), oculomotor nerve (CN III), facial/vestibulocochlear complex (CN VII and CN VIII), and hypoglossal nerve (CN XII) have been described. The records for six patients were reviewed with respect to lesion location, symptoms, surgical approach, and therapeutic considerations. This is the largest series of CMs isolated to CNs reported to date.

RESULTS

Three female patients and three male patients (age range, 28-76 yr; mean age, 41 yr) presented with six CN lesions; four lesions involved the optic chiasm and two involved CN VII and CN VIII. The patients with chiasmatic lesions presented with acute visual deterioration. Both patients with CN VII/CN VIII lesions exhibited acute hearing loss. The level of deterioration suggested CM hemorrhage. Orbitozygomatic craniotomies were performed for chiasmatic lesions, and retrosigmoid craniotomies were performed for cerebellopontine angle lesions. All patients experienced symptom improvement after surgery. One chiasmatic lesion recurred after 2 years and required resection.

CONCLUSION

CN CMs present with site-specific symptoms and require complex surgical techniques for resection. These lesions are frequently symptomatic, because of the eloquence of the tissue of origin. Therefore, all CN CMs should be resected. Subtotal resection uniformly results in disease and symptom recurrence. CN CMs can be resected safely, with preservation of CN function.